Wooden framing fabrication system



Sheet of 5 May 13, 1969 Jfc. JUREIT ET AL I WOODEN FRAMING FABRICATIONSYSTEM Filed Oct. 20.1967

0 Y Y um r M MM 8 g Q g J6 mm M O 0 HC v wt w w i Mimi i 00 Q 0% Y Q OK1/ B N\\ o o g ATTORNEYS May 13, 1969 J. c. JU REl T-ET AL WOODENFRAMING FABRICATION SYSTEM ors Sheet May 13, 1969 J. c. JUREIT ET LWOODEN FRAMING FABRICATION SYSTEM Sheet 015 Filed Oct. 20, 1967 May 13,1969 |.c.JuRE|1 ET AL 3,443,513

WOODEN FRAMING FABRICATION SYSTEM Filed Oct. 20, 1967 MTR F 00 /43 /42/30 I36 /40 as: w 08 I366 /40/?v ua A B as I40F $41 1 LOWER RAISE REVFWD she'et 4 ors U.S. Cl. 100-53 17 Claims ABSTRACT OF THE DISCLOSUREThe fabrication system comprises a conveyor operable to advance a jigtable carrying wooden frame members positioned thereon forming a truss,panel or the like to successively locate the longitudinally spaced buttjoints thereof below a press platen for embedment of nailplates of thetype having a plurality of teeth struck therefrom into the butt joints.The conveyor and press are controlled via a circuit including an indexwheel actuated switch which automatically and sequentially stops theconveyor when successive butt joints are located below the press,actuates the press to embed the nailplates, and restarts the conveyor toadvance the jig table to locate successive butt joints below the press.The index wheel is driven from the conveyor and has a plurality ofrecesses spaced a predetermined distance one from the other about theperiphery thereof representing a predetermined distance of conveyoradvance. A plurality of magnetic pins are inserted in selected recessesof the wheel and project to successively actuate the switch controllingthe conveyor and press. The selectivity of the spacing between adjacentpins permits fabrication of trusses, panels or the like of differentsizes and types.

Background of the invention The present invention relates to a systemfor fabricating wooden trusses, panels or the like and particularly to aconveyor, press and control apparatus therefor whereby nailplates aresuccessively embedded in the spaced butt joints of wooden frame membersforming the trusses, panels or the like.

The wooden building construction industry has recently made tremendousstrides forward with the advent of fabrication techniques wherein buttjoints of wooden frame members forming trusses, panels and the like arefastened together by embedding nailplates of the type having a.plurality of teeth struck therefrom into the joints, typical nailplatesfor this purpose being described in U.S. Patent No. 2,877,520. Previousmethods of applying the nailplates to the butt joints, such as handnailing, employing individual power-operated presses at each joint,etc., have been not only time consuming, laborious and accordinglyexpensive, but do not lend themselves to high production trussfabrication on an assembly line basis.

In conventional fabrication techniques which utilize power-operatedtruss presses, wooden frame members, consisting of elongated chords andcross members, are prepositioned in assembled relation on a jig tablewith connector plates located at opposite sides of the truss, panel orthe like at the butt joints. Thereafter the connector plates are pressedinto the butt joints to fasten the frame members together and form thecompleted truss, panel or the like. A press capable of providing theforegoing action is disclosed in U.S. Patent No. 3,079,607. While thistype of truss press is satisfactory, this press per se and othersemployed for like purposes are not particularly adapted for operation inconjunction with elongated trusses having widely spaced butt jointswherein the press head must be repeatedly raised and lowered and the jigtable carrying the truss manually manipulated to locate nited StatesPatent 3,443,513 Patented May 13, 1969 each of the butt joints of thetruss below the press head or platen for each press operation.

Other conventional fabricating techniques employ a plurality offluid-operated press heads, each mounted on bases movable inlongitudinal and transverse directions whereby the press heads areindividually located relative to each butt joint of a particular sizeand type of truss. The plural presses are then simultaneously actuatedto embed the several nailplates into the butt joints. The press headsthus employed, however, must be accurately and often laboriouslyrepositioned for different sizes and types of trusses, panels or thelike having different locations and spacings between the butt joints.Additionally, in most instances the press heads must be movedtransversely of the truss, panel or the like to permit the same to bewithdrawn from the press, thus necessitating repositioning of theseveral press heads for the completion of each truss, panel or the like,with the result that rapid, efficient and inexpensive fabrication oflarge numbers of even the same size and type of truss cannot berealized.

Summary 0 the invention The present invention provides a uniquefabrication system for automatically or manually forming completedtrusses, panels or the like, hereinafter referred to as trusses. Toaccomplish this, wooden frame members are prepositioned on a jig tableto form a truss and nailplates of the foregoing type are positioned onopposite sides of the butt joints. The jig table is mounted on aconveyor for advancement through and between the heads or platens of apress which is indexed to successively embed the nailplates in the buttjoints as the jig table and frame members are successively advancedthrough the press. A control apparatus including an index wheel isprovided to successively stop the jig table at predetermined positionsalong the conveyor in accordance with the predetermined successivelongitudinal spacing between the butt joints of the prepositioned framemembers to suecessively locate the butt joints thereof in pressingposition below the press platen. In the automatic mode of operation, theconveyor is stopped, the upper press platen is lowered to press thenailplates into the butt joints and raised therefrom, and the conveyoris advanced, in response to sequential actuation of the control circuitactuating index wheel which rotates predetermined distances proportionalto the successive longitudinal distances between the spaced butt joints.

Additionally, the index wheel of the present invention can be readilyprogrammed to advance the conveyor and control the press to embed thenailplates in trusses of different sizes and types having variouslyspaced butt joints. The index wheel has a plurality of cylindricalrecess spaced predetermined distances one from the other about theperiphery of the wheel corresponding to a predetermined advance of theconveyor. A plurality of pins are provided for releasable magneticengagement in selected recesses whereby the spacing between the pins isa whole multiple of the peripheral spacing between the recesses. Thewheel and pins are arranged to actuate a switch which cycles theconveyor stop, the press operation, and the conveyor advance, the pinsactuating the switch in accordance with the predetermined spacingbetween the butt joints.

The index wheel is driven from the conveyor whereby conveyor and wheelpositions are synchronized. Accordingly, the wheel position relative tothe actuating switch is proportional o the distance the conveyor hasadvanced, the initial wheel setting or arrangement of the pins on thewheel corresponding to the initial conveyor position. After completelyfabricating the truss and at the end of the conveyor advance whereuponthe completed truss is unloaded, the jig table actuates limit switchesto retract the jig table along the conveyor to its initial position andthus repositions the index wheel to its original position. Additionalframing members can then be assembled thereon for advancement throughthe press as before. In this manner, the press control system can be setfor a truss of a particular size and type and a plurality of liketrusses can be subsequently formed without readjusting the conveyor andpress setting.

To program the press control system for trusses of different sizes andtypes, the pins in the index wheel, being magnetically secured Withinthe recesses, can be readily and easily withdrawn therefrom forreinsertion in other selected recesses to thereby vary the spacingbetween adjacent pins. Since the latter spacing is a function of theconveyor advance, the known longitudinal spacing between the butt jointsof different sizes and types of trusses can be set into the index wheelby correlating such known spacing between the butt joints and thespacing between adjacent pins.

Accordingly, it is an object of the present invention to provide afabrication system for successively embedding nailplates into the spacedbutt joints of wooden frame members forming a truss, panel or the like.

It is another object of the present invention to provide a fabricationsystem which is readily and easily adjusted to form trusses, panels orthe like of different types, sizes and shapes.

It is a further object of the present invention to provide a trussfabrication system which can be operated automatically or manually asdesired.

It is still another object of the present invention to provide a trussfabrication system which is simple in construction, rapid in operationand inexpensive to manufacture.

It is another object of the present invention to provide a trussfabrication system including a press, conveyor and control thereforwherein the press and conveyor can be indexed for a particular size andtype of truss and any number of identical trusses fabricated withoutresetting the press for each truss run.

It is still a further object to provide a control actuating index wheelwhich can be readily and easily adjusted to a plurality of selectedactuating positions.

It is still a further object of the present invention to provide acontrol actuating index wheel having a plurality of predetermined spacedpositions therealong and a plurality of actuating elements easily andreadily secured in selected locations in said spaced positions.

These and further objects and advantages of the invention will becomemore apparent upon reference to the following specification, claims andappended drawings.

Brief description of the drawing figures FIGURE 1 is a side elevationalview of a general arrangement of a fabrication system constructed inaccordance with the present invention and shown with portions brokenaway for ease of illustration;

FIGURE 2 is an enlarged fragmentary plan view thereof illustrating a jigtable carrying a truss on a conveyor in pressing position with only thelower press platen being shown;

FIGURE 3 is a transverse sectional view thereof taken about on line 3-3of FIGURE 2;

FIGURE 4 is a side elevational view of the index wheel and cabinettherefor;

FIGURE 5 is a transverse elevational view of the index Wheel and itsconnection with the conveyor drive with portions thereof broken away forease of illustration;

FIGURE 6 is a fragmentary side elevational view of the drive connectionbetween the index wheel and the conveyor drive taken about on line 6-6of FIGURE 5;

FIGURE 7 is an enlarged fragmentary view of the actuating switch and pinassembly on the index wheel taken about on line 7-7 of FIGURE 5;

FIGURE 8 is a transverse cross sectional view thereof tak n a out on ine8-8 of FIGURE FIGURE 9 is a fragmentary enlarged perspective v1ew of thepin assembly on the index wheel;

FIGURE 10 is an enlarged fragmentary elevational view of a conveyorchain tensioning device;

FIGURE 11 is a plan view thereof;

- FIGURE 12 is a transverse elevational view of another form of theconveyor;

FIGURE 13 is a schematic illustration of a fluid-operated press;

FIGURE 14 is an electrical hydraulic schematic diagram illustrating thefluid controls for the press and conveyor drive; and

FIGURE 15 is a schematic illustration of the electrical controls for thepress system of the present invention.

Description of the preferred embodiment Referring to FIGURE 1, there isshow the fabrication system of the present invention comprisinggenerally a conveyor 10, a press 12 located substantially mediallybetween the ends of conveyor 10 and having upper and lower press platens14 and 16 respectively, a control system including a cabinet 18 housingan index wheel 20 and a control console 22 housing the electricalcircuitry to be described and a suitable control panel 23. Conveyor 10has a pair of upstanding legs 24 space longitudinally therealong, thelower ends of legs 24 being supported in footings 26 of the usual typeand the upper ends thereof supporting four laterally spaced elongatedparallel beams 28 as seen in FIGURE 2. Beams 28 form a pair oftransversely spaced conveyor sections 30 having longitudinally spacedrollers 32 journaled at opposite ends in the associated beams 28. Anelongated central member 34 is located between conveyor sections 30between the innermost beams 28 thereof and provides a guideway receivingconveyor drive chain 36. A hydraulic motor 38 drives chain 36 aboutsuitable idler rollers 40 mounted on centrally disposed stanchions 39located beyond opposite ends of conveyor 10 and about rollers 44 ofchain tensioning devices 42 mounted on stanchions 39. As best seen inFIGURES 10 and 11, tensioning devices 42 each comprise a pair of arms 46pivotally mounted adjacent their upper ends to the upper ends ofstanchions 39 and pivotally mounting roller 44 therebetween as by pin47. A rod 48 is pivotally mounted to the lower end of stanchion 39 andextends through a pin 49 pivotally mounted between the lower ends ofarms 46. A spring 50 is carried on the end of rod 48 and bears againstpin 49 to bias arms 46 in a direction to tighten chain 36.

As best seen in FIGURE 2, a jig table 52 is carried on rollers 32 andhas a pair of depending lugs (not shown) which connect with oppositeends of chain 36 whereby jig table 52 is driven along conveyor 10 bychain 36. Wooden framing members 54 are prepositioned on jig table 52 toform a truss, the framing members 54 being held in suitable positions onjig table 52 by a plurality of clamps (not shown) which may be of thetype illustrated in US. Patent No. 3,241,585. Nailplates 56 are providedat the butt joints of the truss on opposite sides thereof and, as seenin FIGURE 2, the plates 56 to the right of press 12 have been embeddedin the butt joints while the plates 56 to the left of press 12 remain tobe embedded, the jig table 52 being advanced along conveyor 10 in thedirection from left to right.

Another form of conveyor 10, illustrated in FIGURE 12 and which is Widerthan the conveyor illustrated in FIGURES 1 and 2, may be employedherewith to accommodate trusses having larger widths requiring largerjig tables. This form of conveyor comprises a pair of transverselyspaced legs 60 supporting a plurality of transversely extending members62 at longitudinally spaced positions along the conveyor. The lower endsof legs 60 are suitable secured in footings as in the previous form anda transverse member 64 joins the transversely spaced legs and provides asupport for an elongated beam 66 h ch s pports chain 36 below theconveyor. In this m stance, four longitudinally extending conveyorsections 68 are provided, each having a pair of elongated transverselyspaced beams 70 pivotally mounting a plurality of longitudinally spacedrollers 72 therebetween. A central support beam 74 is mounted on members62 to guide chain 36 along the top of the conveyor.

Referring now to FIGURES 4-9, the control system includes the indexwheel 20 which is driven in rotation by chain 36 and arranged tosuccessively actuate a micro-- switch 76. As seen in FIGURE 5, wheel 20is mounted for rotation on a frame assembly, generally indicated 77,comprising a pair of longitudinally spaced upright stanchions 78suitably mounted on footings 26 as by angle brackets 80, stanchions 78being located adjacent one side of conveyor and suitably mountingcabinet 18. Frame 77 includes a transversely extending base frame 80suitably connected at its inner end to a pair of upright stanchions 82which lie below conveyor 10 adjacent the centerline thereof. Base frame80 mounts a pair of bearings 84 and opposite end portions of shaft 86are journaled in bearings 84. A drive coupling 87 connects the outer endof shaft 86 with the inner end of an axially reduced shaft 88, the outerend of the latter driving reduction gearing 89 secured to stanchions 78within cabinet 18. A reduction gearing output shaft 90 is keyed to thehub 91 of wheel 20. A drive sprocket wheel 92 is suitably keyed on theinner end of shaft 86 and a pair of idler sprocket wheels 93 arejournaled adjacent the upper ends of stanchions 82. A pair of idlerwheels 94 are journaled on stanchions 82 below idler sprocket wheels 93and a third idler wheel 96 is journaled in a cross frame 98 secured atopposite ends to stanchions 82, idler wheel 96 being located above thedrive sprocket wheel 92. Chain 36 extends longitudinally in threadingengagement with drive and idler sprocket wheels 92 and 93. Respectiveidler wheels 96 and 94 maintain chain 36 in driving engagement withspocket wheel 92 and in engagement with sprocket wheels 93. Accordingly,when 'motor 38 drives chain 36 about rollers 40 and 44 in a clockwisedirection as seen in FIGURE 1 to advance jig table 52 along conveyor 10,index wheel is simultaneously rotated therewith through drive sprocketwheel 92, shafts 86 and 88, and reduction gearing 89 for purposes aswill presently become clear.

As seen in FIGURES 5, 7, and 8, a microswitch 76 is mounted on a bracket106 secured to the inner wall of cabinet 18, bracket 106 being mountedfor vertical adjustment within cabinet 18 by screws 108 and switch 76being mounted on bracket 106 for longitudinal adjustment by bolts 110whereby depending switch actuating arm 112 is adjustably positionedrelative to wheel 20. Switch 76 is a one-way actuated microswitch whichenergizes a circuit to automatically advance jig table 52 along conveyor10, stop jig table 52, lower and raise press platen 14 to embednailplates 56, and restart the conveyor to further advance jig table 52as will be described hereinafter.

As seen in FIGURES 4, 7, 8, and 9, wheel 20 has a plurality ofcylindrical recesses 114 opening through the outer face and adjacent theperiphery thereof, recesses 114 being spaced a predetermined distanceone from the other. A plurality of pins 116 having cylindrical bases 118are provided for insertion and snug retention in selected recesses 114for purposes to be described. Each pin 116 has an elongated shankportion 120 having a threaded inner end (not ShOWn) which threadedlyengages within a complementary recess in base 118 whereby shank portions120 of pins 116 project from the face of wheel 20. A jam nut 122 securesthe connection between pin 116 and base 118. The surface of shankportion 120 is preferably serrated and engages against roller 124 on theend of arm 112 to actuate switch 76.

It is a significant feature of the present invention that pins 116 arereleasably secured in the selected recesses 114 in a manner whichprovides for the ready and rapid withdrawal of pins 116 therefrom andreinsertion of the same into other selected recesses. To this end, wheel20 is formed of a ferromagnetic material, preferably steel, and bases118 of pins 116 are permanent magnets, preferably formed of Alnico 5.Accordingly, to insert in or rearrange the pins on wheel 20 to providefor the actuation of switch 76 in a desired timed sequence, pins 116 canbe readily and rapidly withdrawn from or inserted in selected recesses114 as the magnetic attraction between bases 118 thereof and wheel 20assures secure retention of the pins in the recesses as well as easywithdrawal of the pins therefrom. An opening 126 is provided through therear face of wheel 20 into each recess 114 to equalize the pressure onopposite sides of the pin, thereby facilitating the insertion andwithdrawal of each pin 116.

It is also a feature hereof that switch 76 is successively actuated inresponse to consecutive predetermined advances of jig table 52 alongconveyor 10 distances equal to the distances between successive buttjoints to thereby locate each butt joint successively below press platen14 for embedment of the associated nailplates. Switch 76 is successivelyactuated in accordance with the predetermined spacing between theperipherally next adjacent pins 116. The spacing between next adjacentrecesses 114 is proportional to a predetermined distance advanced by jigtable 52 on conveyor 10 through the index wheel drive mechanism andreduction gearing 89. In the prefer-red form, reduction gearing 89provides for a rotary advance of index wheel 20 equal to the peripheraldistance between the centers of the next adjacent recesses 114 for eachone foot of jig table travel on the conveyor 10. Accordingly, if pinsare inserted in successive next adjacent recesses 114, switch 76 wouldbe successively actuated for each one foot of advance of the jig tablealong conveyor 10. Similarly, locating pins 116 in every other recesswould provide for successive actuation of switch 76 for every two feetof jig table advance. In this manner, trusses of various sizes and typeshaving various spacing between their butt joints can be readilyfabricated by locating pins 116 in selected recesses spaced one from theother in accordance with the spacing between the butt joints, it beingunderstood that platens 14 and 16, in the preferred form, have a widthextending in the longitudinal direction of the conveyor at least equalto one foot.

As illustrated in FIGURES 13 and 14, an electrically controlled fluidcircuit is provided and arranged in controlling relation to conveyordrive motor 38 and to the fluid actuated press 12. Press 12 isillustrated schematically by the dashed lines, the upper platen 14 beingmovable with respect to the fixed lower platen 16 by a pair offluid-operated pistons and cylinders 130 and 131, respectively.Cylinders 131 are fixed on opposite ends of movable platen 14 and a pairof fluid lines 132 and 133 (FIGURE 14) alternately supply pressurizedfluid to opposite sides of cylinders 131 to reciprocate platen 14. Fluidfrom a reservoir 134 is pressurized by an electrically driven pump 135.Fluid from pump 135 flows to a fourway, three-position control valve 136via a conduit 137. Valve 136 is biased to the illustrated neutralposition by a pair of springs 138 whereat input conduit 137 communicatesdirectly with an intermediate conduit 139 connected to a like four-way,three-position control valve 140. Valve 140 is similarly biased to theillustrated neutral position whereat conduit 139 communicates with areturn conduit 141 emptying into reservoir 134.

A pair of solenoids 136L and 136R are arranged to shift valve 136 toalternately lower and raise press platen 14 and are actuated in a mannerto be described. Actuation of solenoid 136L shifts valve 136 to theright as seen in FIGURE 14 to provide pressurized fluid via conduits137, 142, and 133 to the lower sides of cylinders 131 to lower platen 14with pressure fluid exhausting from the upper sides of cylinders 131through conduits 132, 143, 139 and 141 to reesrvoir 134. Actuation ofsolenoid 136R shifts valve 136 to the left to provide pressurized fluidvia conduits 137, 143, and 132 to the upper sides of cylinders 131 toraise platen 14 with pressure fluid exhausting from the lower sides ofcylinders 7 131 via conduits 133, 142, 139, and 141 to reservoir 132.

A pair of solenoids 140Rv and 140F are arranged to shift valve 140 andare actuated in a manner to be described to alternately operate motor 38in the forward or reverse directions, thereby respectively advancing orretracting jig table 52 along conveyor 10. It will be noted withreference to the control circuit hereinafter described that valve 138 isalways in the neutral position when the conveyor is being eitheradvanced or retracted and that valve 140 is always in the neutralposition when press platen 14 is being lowered or raised. Actuation ofsolenoid 140F shifts valve 140 to the left as seen in FIGURE 11 toprovide pressurized fluid via conduits 137, 139, and 144 to motor 38 todrive conveyor chain 36 forwardly with exhaust fluid returning toreservoir 132 via conduits 145 and 141. Actuation of solenoid 140Rvshifts valve 140 to the right to provide pressurized fluid via conduits137, 139 and 145 to motor 38 to drive the conveyor chain 36 in thereverse direction to retract jig table 52 with exhaust fluid returningto reservoir 132 via conduits 144 and 141.

The electrical circuit disclosed in FIGURE is arranged to sequentiallyshift valves 136 and 140 to advance jig table 52 along conveyor 10, stopjig table 52, lower and raise platen 14, and restart conveyor 10, torepeat the foregoing conveyor-press cycle successively as the buttjoints are successively located below platen '14 and to retract jigtable 52 along conveyor 10 after the truss is completely fabricated andremoved therefrom. The control circuit is illustrated in a detachedcontact mode wherein the various relays, represented by circles, openand close associated contacts in a manner to be described, normally openand closed contacts being denoted by the vertical pairs of parallellines and the slashed pairs of vertical parallel lines respectively,With the contacts having letter suflices corresponding to the lettersuflices of their actuating relays. A power source S is provided acrossa pair of supply lines 146 and 148, supply line 146 including a suitablefuse 149 and an emergency conveyorpress stop pushbutton switch 150which, when depressed as illustrated, breaks whatever completed circuitis controlling the press or conveyor operation. To start the fabricatingsystem, fluid motor 135 is actuated by momentarily depressing a motorstart pushbutton 151 which completes a circuit through motor startercoil M via lead lines 146, 152, a normally closed motor stop pushbutton153 and lead line 148. Energization of coil M closes normally opencontact 154 which maintains the motor circuit energized for continuousoperation after motor start button 151 is released. Actuation of fluidpump 135 pressurizes the circuit as described hereinbefore whereby fluidis maintained available for subsequent operation of press cylinders 131and hydraulic motor 38.

A brake circuit is energized across lead lines 146 and 148 and comprisesa bridge rectifier 160 having a potentiometer 162 across the outputthereof. Potentiometer arm 164 is connected in series with contacts 166Fand 168R and capacitor 170 to actuate a brake B connected in parallelwith capacitor 170, brake B being suitably connected to the driveconnection between motor 38 and chain 36 to brake jig table 52 as thelatter is advanced or retracted along conveyor 10.

Frame members 54 are now prepositioned and clamped, by means not shown,on jig table 52 with nailplates 56 located on opposite sides of the buttjoints. To commence fabrication in the automatic mode of operation andto initially advance jig table 52 along conveyor 10, a pushbutton 172 ismomentarily depressed to energize a circuit via lead lines 146, 174 and148 which actuates the automatic mode relay 176A, which in turn closesnormally open contacts 178A, 179A, and 180A. Closing of contacts 178Aand 179A energizes a circuit via lead lines 146, 182, and 184, throughnormally closed contacts 186L and 188R, through a pair of normallyclosed limit switches 190 and lead lines 192 and 148 to 8 actuatesolenoid F and a relay 194F. Actuation of relay 194E opens normallyclosed contact 166F to deenergize the brake circuit, thereby releasingchain 36 for forward travel along conveyor 10. Actuation of solenoid140F shifts valve 140 to the left as seen in FIGURE 14 to drive motor 38and chain 36 in the forward direction as hereinbefore described, therebyadvancing jib table 52 along conveyor 10 toward press 12. It will benoted that closing of contacts 178A energizes an automatic mode holdingcircuit via leads 146, 182, and 196, through normally closed contact198R and lead lines 174 and 148 to maintain relay 176A actuated and anautomatic mode indicator light 200 lit on console 22 via a lead line 202after automatic mode pushbutton 172 has been released.

Wheel 20 is initially synchronized with the conveyor advance in a manneras will presently become clear to actuate rnicroswitch 76 when the firstof the butt joints of a particular size and type of truss is locatedbelow the upper press platen 14, it being understood that subsequentswitch actuating pins are located in selected recesses 114 ashereinbefore described and behind the first pin location. Actuation ofswitch 76 energizes a circuit via lead lines 146 and 182, closed contact178A, lead lines 184, 204, 206, 208, 209, and 148, to actuate a presslowering relay 210L and a pneumatic timing relay 212. Actuation of relay210L opens normally closed contacts 186L, thereby deenergizing solenoid140F whereby valve 140 is springreturned to the illustrated neutralposition to interrupt the hydraulic circuit to motor 38. Opening contact186L also deenergizes relay 194F whereby contacts 166E return to thenormally closed position to actuate brake B to stop forward movement ofjib table 52 and prevent further forward coasting thereof. Actuation ofrelay 210L closes normally open contacts 214L to energize a holdingcircuit via lead line 216, a normally closed press stop button 218,normally closed press raise pushbutton switch 220, a normallypressure-actuated switch 222, and lead lines 208, 206, 209, and 14 8 tomaintain relays 210L and 212? actuated as pins 116 advance slightlybeyond the actuating position of switch 76.

Actuation of relay 212P closes normally open switch 224 after a shorttime delay, normally open contacts 226L being closed in response toactuation of relay 210L. Solenoid 136L is thus energized after a shorttime delay via a circuit comprising lead lines 148, 228, closed switchand contacts 224 and 226L respectively, and lead line 148. As seen inFIGURE 14, valve 136 is thus shifted to the right to complete the fluidcircuit from reservoir 134 to the lower sides of cylinders 131, therebyloiwering press platen 14 as described before.

At the bottom of the press stroke, interconnected pressure-actuatedswitches 222 and 230 reverse momentarily to actuate a press raisingrelay 232R via a circuit comprising lead line 146, switch 218, leadlines 216, 234, normally closed press lowering pushbutton switch 236, alimit switch 238 which is open only when press platen 14 is raised, leadline 240, pressure switch 230 which is closed at the end of the pressdownward stroke, and lead lines 242 and 148'. Momentarily opening switch222 breaks the press lowering holding circuit to deenergize relays 210Land 212P, thereby opening contact 226L and switch 224 to deenergizesolenoid 136L and opening contacts 186L and 214L. Simultaneous actuationof relay 232R opens normally closed contact 188R to open the circuitthrough the conveyor forwarding solenoid 140F and relay 194F. Relay 232Ralso closes normally open contact 244R to energize a press raisingholding circuit via lead lines 146, 216, 234, 246, 242, and 148 tomaintain relay 232R energized after switch 230 opens at the beginning ofthe press upstroke. Relay 232R also closes normally open contacts 248Rto energize solenoid 136R via a circuit comprising lead lines 146, 250and 148. As seen in FIGURE 14, valve 136 is shifted to the left and afluid circuit is completed from reservoir 134 to the upper sides ofcylinders 131 to raise press platen 14.

At the end of the upstroke of platen 14, the latter opens limit switch238 to deenergize the press raising holding circuit and relay 232Rwhereby contacts 244R and 248R are returned to their normally openposition and contact 188R is returned to its normally closed position.Opening contact 248R deenergizes solenoid 136R whereby valve 136 isbiased to its neutral position by springs 138 as illustrated in FIGURE11. The return of contact 188R to the normally closed position energizesthe foregoing described circuit to the conveyor forwarding solenoid 140Fand relay 194F, whereby normally closed contact 166F is opened todeenergize brake B. Valve 140 is again shifted to the left to pressurizemotor 38 to advance the jig table 52 along the conveyor.

It will be appreciated that the foregoing described cycle of operation,that is, conveyor advancing, stopping, press lowering and raising, andconveyor advancing, is repeated as many times as the number of pins inwheel 20 which corresponds to the number of longitudinally spaced buttjoints in the truss. As hereinbefore described, the spacing of pins 116about the index wheel 20 is proportional to the distance that the jigtable 52 advances on conveyor such that switch 76 is successivelyactuated to initiate the conveyor stopping, press lowering and raising,and conveyor restarting operations as the butt joints are successivelypositioned in press position below platen 14. For example, for a trusshaving three butt joints with the intermediate butt joint spaced tenfeet behind the initial butt joint and the last butt joint spaced ninefeet behind the intermediate joint, the pins 116 are arranged on thewheel 20 such that the first pin is inserted in recess 114 which wouldactuate switch 76 when the first butt joint is in position below platen14. The next pin would be inserted in a selected recess 114corresponding to a conveyor advance of ten feet which would, in thepreferred form, locate such next pin ten recesses behind the firstrecess. The third pin would accordingly be located in a recesscorresponding to an additional conveyor advance of nine feet and wouldtherefore be located in the recess nine recesses behind the intermediatepin. In this manner, trusses of different types having different sizesand spacing between the butt joints may be fabricated.

After the truss is completely formed, jig table 52 is continuouslyadvanced along conveyor 10 until it actuates a pair of normally closedlimit switches 190 located adjacent the end of conveyor 10. Openingswitches 190 deenergizes solenoid 140F and relay 194F to return contact166F to its normally closed position, thereby braking and stopping thejig table advance. The completed truss can then be removed from jigtable 52.

To reverse the jig table travel along conveyor 10 and retract the sameto the initial position, a jig drum switch 252 is closed by a pressoperator to energize a circuit via leads 146, 254, and 256, closed limitswitches 258 and lead line 142 to actuate conveyor reversing relay260'Rv and solenoid 140Rv. Relay 260Rv opens normally closed contact168R to release brake B and solenofid opens contact 198Rv to deenergizethe automatic mode holding relay 176A and 140Rv shifts valve 140 tocomplete a fluid circuit from reservoir 134 to drive motor 38 in thereverse direction. Motor 38 accordingly retracts jig table 52 alongconveyor 10 through press 12 in the reverse direction until it openslimit switches 258 located at the forward loading end of the conveyor 10to deenergize relay 260Rv and solenoid 140R whereby contact 168R isclosed to energize brake B and contact 198Rv is again closed. Jig table52 is thus repositioned at the loading end of the conveyor and indexwheel 20 is simultaneously rotated therewith in the oppositecounterclockwise direction as seen in FIGURE 4 to its initial positionfor the start of another run fabricating a truss of similar size andtype having similar spacing between the butt joints. In the automaticmode, only start pushbutton 172 and drum switch 252 need be manuallyoperated.

The complete truss fabrication cycle can be operated manually. Moreover,the manual controls may be employed to locate the initial or first pinposition on wheel 20 in an initial test run and thereafter a largenumber of like trusses may be fabricated in the automatic mode ashereinbefore described. To cycle the conveyor and press manually, jigdrum switch 252 is closed to energize solenoid F and relay 194F via acircuit comprising lead lines 146, 254, 192, and 148. The jig table 52advances from the loading position as before with wheel 20 rotatingtherewith until the first butt joint is located below press platen 14,at which time the press operator opens jig drum switch 252 to deenergizesolenoid 140F and relay 194F. With wheel 20 thus located, the first pin116 is inserted in the recess 114 Which locates the pin for actuation ofswitch 76. To lower the press platen, pushbutton 236 is depressed toenergize relays 210L and 212P via the circuits comprising lead lines146, 216, 206, 208, 209, and 148, valve 136 shifting as before to lowerplaten 14.

At the bottom of the downstroke, switches 222 and 230 momentarilyreverse to deenergize the relays 210L and 212P and button 220 isdepressed to complete a circuit via lead lines 146, 216, 234, 264, 242,and 148, to energize relay 232R. Relay 232R operates to shift valve 136as before and limit switch 238 opens at the end of the upstroke ofplaten 14 to deenergize relay 232. Drum switch 252 is again manuallyclosed by the operator to complete the circuit through solenoid 140F andrelay 194 to further advance jig table 52 along conveyor 10 such thatthe next butt joint is located below press platen 14. The placing of pin116 in wheel 20 and manual operation of the press and conveyor cycle isrepeated for as many butt joints as there are in the truss whereby, atthe completion of the fabrication cycle, pins 116 are located inselected recesses 114 to automatically stop the conveyor and initiatethe press cycle for any number of the same type and size of trusses thatare to be fabricated in the automatic mode. Alternately, subsequent pinsmay be inserted in selected recesses behind the first pin in accordancewith the measured spacing of the butt joints behind the first butt jointinasmuch as the advance of the conveyor and wheel are synchronized forproportionate advancement in a predetermined ratio.

It will thus be appreciated that any numer of like trusses, panels orthe like may be fabricated after the pins in the index wheel areinitially set to selected positions corresponding to the known distancesbetween the spaced butt joints.

It is also significant that the press control system can be readily,easily and rapidly set up to accommdate trusses, panels or the likehaving different spacing between the butt joints thereof whereby highproduction rates can be attained, not only for like trusses, panels orthe like, but also for a wide range of size, type and configuration ofdifferent trusses, panels or the like.

What is claimed and desired to be secured by United States LettersPatent is:

1. A fabrication system for successively embedding connector plates inthe spaced butt joints of prepositioned wooden framing members formingtrusses or the like comprising means for supporting the Wooden framingmembers including a conveyor, press means located at a point along saidconveyor and defining a press position, means for advancing the membersalong said conveyor for movement thereof through said press position,means arranged in controlling relation to said press means includingindex means operable in response to the advancement of the members alongsaid conveyor successive distances equal to the distances betweenconsecutive butt joints to successively actuate said press means andpress the connector plates in the butt joints as the latter are advancedthrough the press position.

2. A fabrication system according to claim 1 wherein said index means isarranged in controlling relation to said advancing means to successivelystop the latter thereby successively locating the butt joints in thepress position.

3. A fabrication system according to claim 2 wherein said control meansincludes switch means and said index means includes a member mounting aplurality of spaced switch actuating elements, the spacing betweenadjacent actuating elements being proportional to the predeterminedspacing between the butt joints, and means providing for relativemovement between said switch means and said member for successiveactuation of said switch means.

4. A fabrication system according to claim 3 wherein said member has aplurality of mounting positions for said elements, magnetic meansreleasably retaining said elements in said mounting positions, saidelements being movable between mounting positions to selectively varythe spacing between adjacent elements.

5. A fabrication system according to claim 4 wherein adjacent mountingpositions are spaced a predetermined distance on said memberproportional to a predetermined distance of conveyor advance whereby thespacing between adjacent elements is a whole multiple of the spacingbetween the associated positions.

6. A fabrication system according to claim 2 wherein said advancingmeans includes fluid motor means and a fluid circuit therefor havingvalve means controlling said fluid motor means, said index meansincluding switch means arranged in controlling relation to said valvemeans to shift the latter and stop said fluid motor means.

7. A fabrication system according to claim 2 wherein said conveyoradvancing means includes a fluid motor and said press means includes apress platen and at least one fluid actuated cylinder operable to movesaid platen toward and away from the joints, said control meansincluding a fluid control circuit having electrically actuated valvesoperably connected with said fluid motor and said cylinder, anelectrical circuit arranged in controlling relation to said valves, andswitch means in said electrical circuit, said indexing means beingoperable to actuate said switch means to energize said electricalcircuit to shift said valves to stop the advance of the members alongthe conveyor and move the press platen toward and away from the joint.

8. A fabrication system according to claim 2 wherein said conveyoradvancing means includes a fluid motor and said press means includes apress platen and at least one fluid actuated cylinder, said controlmeans including a fluid control circuit having valve means operablyconnected with said fluid motor and said cylinder, and means operable toshift said valve means between positions operable to move said platentoward and away from the joints and to selectively stop and advance themembers along said conveyor, said valve shifting means being operable inresponse to the movement of said press platen away from the joints toadvance the members along the conveyor.

9. A fabrication system according to claim 8 wherein said valve meansincludes a pair of valves connected in series and respectivelycontrolling said fluid motor and said press cylinder.

10. A fabrication system according to claim 8 wherein said control meansincludes means located adjacent the end of said conveyor operable toshift said valve means to stop the advancement of the members along theconveyor.

11. A fabrication system according to claim 1 wherein said control meansincludes switch means and said index means includes a rotatable wheel,said wheel mounting a plurality of spaced actuating pins about theperiphery thereof, the spacing of successive adjacent pins one from theother being proportional to the successive predetermined spacing betweenthe joints, and means drivingly connecting said wheel to said conveyoradvancing means for rotating said wheel to successively actuate saidswitch.

12. A fabrication system according to claim 11 wherein said wheel has aplurality of spaced recesses opening through a side face and adjacentthe periphery thereof for receiving said pins, and magnetic means forreleasably retaining said pins in said recesses, said pins being movablebetween the recesses to selectively vary the spacing between adjacentpins.

13. A fabrication system according to claim 12 wherein adjacent recessesare spaced a predetermined circumferential distance about said wheelproportional to a predetermined distance of conveyor advance whereby thespacing between adjacent pins is a whole multiple of the spacing betweenthe associated recesses.

14. A fabrication system according to claim 1 wherein said press meansincludes a press platen and at least one fluid actuated cylinderoperable to move said platen toward and away from the joints, saidcontrol means including a fluid control circuit having electricallyactuated valve means operably connected with said cylinder, anelectrical circuit arranged in controlling relation to said valve means,and switch means in said electrical circuit, said indexing means beingoperable to actuate said switch means to energize said electricalcircuit and shift said valve to move the press platen toward and awayfrom the joint.

15. A control apparatus for a machine system having sequencedoperations, comprising switch means, a wheel having a plurality ofswitch actuating positions spaced about the periphery thereof, thespacing between successive positions being proportional one to theother, means for rotating said wheel, a plurality of pins releasablyengageable with said wheel in said switch actuating positions thereofand having shank portions adapted to project from said wheel to actuatesaid switch means, and magnetic means cooperating between said wheel andsaid pins releasably retaining said pins in selected positions aboutsaid wheel whereby said switch means may be successively actuated in apredetermined manner to sequence the machine system.

1 6. A control apparatus according to claim 15 wherein said switchactuating positions comprise recesses formed in said wheel and openingthrough a side face thereof, said pins having base portions adapted forinsertion in said recesses.

17. A control apparatus according to claim 16 wherein said base portionsare permanent magnets and said wheel is formed of a ferromagneticmaterial.

References Cited UNITED STATES PATENTS 2,272,009 2/1942 Keller et al-222 XR 3,125,947 3/1964 Hubin 100-222 XR 3,282,391 11/1966 Solet et al19819 3,390,627 7/1968 Levkovitz 100215 XR BILLY I WILHITE, PrimaryExaminer.

UNYEED S'iA'lES PATEL OFFICE fa/0:1]: T T T CERTiFlLAliL Gr CQRRECTLQRPatent No. 3 4435l3 Dated y 1-969 lnventorfi's) John C. Jureit and OscarCsakvarv It is certified that error appears in the above-identifiedpatent and that said Letters Patent are hereby corrected as shown below:

2 Column 2, line 52, "recess" should read recesses Column 4 line 16,"show" should read shown Column 4 line 25 "space" should read spacedColumn 6, line 71 "reesrvoir" should read reservoir Column 8 line 7 "jit)" should read jig Column 8 line 32 "j ih" should read jig Column 9,line 21 delete "the" Column 9, line 57 delete "solenoid"; Column 9, line59, after "and" insert solenoid Column 10, line 44, "numer" should readnumber SIGNED AND SEALED MAY 121970 (SEAL) .Attest:

M Flewhmh Zi 'L.-.ZYL AM WT-QUEER, 1m Au u Offi Commissioner of Patents

